* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: Arial;
  background: #0d1117;
  color: white;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.container {
  background: #161b22;
  padding: 25px;
  border-radius: 10px;
  width: 320px;
  text-align: center;
  box-shadow: 0 0 10px rgba(0,0,0,0.5);
}

h1 {
  margin-bottom: 15px;
}

.input-section {
  display: flex;
  gap: 10px;
}

input {
  flex: 1;
  padding: 8px;
  border: none;
  border-radius: 5px;
}

input:focus {
  outline: none;
  border: 2px solid #1db954;
}

button {
  padding: 8px 12px;
  background: #1db954;
  border: none;
  border-radius: 5px;
  cursor: pointer;
}

button:hover {
  opacity: 0.8;
}

ul {
  margin-top: 15px;
  list-style: none;
}

li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #0d1117;
  padding: 10px;
  margin-top: 8px;
  border-radius: 5px;
  transition: 0.2s ease;
}

li:hover {
  transform: scale(1.02);
}

li button {
  background: red;
  color: white;
  border: none;
  padding: 5px;
  border-radius: 5px;
  cursor: pointer;
}

li button:hover {
  background: darkred;
}

.done {
  text-decoration: line-through;
  opacity: 0.6;
}